Writing in his Twitter page Saturday, Prime Minister Edi Rama said he had accepted Interior Minister Fatmir Xhafaj’s resignation, without giving any explanation.

Xhafaj resigned after a recent major operation that arrested more than two dozen suspects of organized crime rings, including two former lawmakers of the governing Socialist Party.

Xhafaj wrote on the Interior Ministry’s Facebook page that he had willingly resigned and cited his agency’s “very important successes in strengthening the rule of law in the country.”

Rama then nominated Sander Lleshi, a former military official, as the new interior minister, saying he will bring “new positive energy” to the post. Lleshi must be approved by the president and parliament.

Fighting organized crime, drug trafficking and corruption are top priorities for Albania, which is looking to launch full membership negotiations with the European Union next year. Despite a government crackdown, Albania still remains a hotbed for marijuana and other drug smuggling and a haven for drug money laundering.

The opposition Democratic Party hailed Xhafaj’s resignation as “an important step in our fight to clean politics of crime.” It had accused Xhafaj of supporting his brother’s drug-related activities, a claim Xhafaj had denied. In April, his brother turned himself to Italian authorities to serve a 2002 sentence for drug trafficking.

Xhafaj’s predecessor, Saimir Tahiri, is being investigated for graft and alleged involvement in a drug trafficking ring.